Science – Mission to Hubble

Science and the Human Spirit

About two weeks ago, the crew of seven astronauts that is preparing for the Hubble servicing mission (SM4) invited me to come to the Johnson Space Center (JSC) to give them a series of talks on Hubble science. I was, of course, very happy to oblige. I arrived to JSC on October 20, and the entire morning of October 21 was reserved for my presentation. The fact that the crew were able to accommodate such a presentation in their busy schedule was the result of the delay in SM4, which was originally planned to take off on October 14.

So here I was, arriving on a date on which if all would have gone right the crew would have been in space!

Even though I believe that I give reasonably good talks, I thought that the crew must regard my presentation as a rather poor consolation prize. Still, I was extremely happy to see again Scott Altman, Gregory Johnson, Megan McArthur, Michael Good, Andrew Feustel, and my old friends John Grunsfeld and Mike Massimino. These are a real life “magnificent seven.”

As expected, the crew members did not hide at first their disappointment from the fact SM4 had to be postponed, and neither did I. Yet, as my presentation of a series of recent HST results went on, they became more and more engaged. They started bombarding me with questions about how the new instruments (that will be installed on board HST during SM4) would contribute to the scientific questions I was discussing. By the time I finished, none of us was looking back. We were all again sharing the excitement of the grand things that the telescope would do after SM4.

On the way to the airport Massimino told me that my presentation helped renew the enthusiasm of the crew towards the mission. I could not have asked for a bigger compliment.

Hubble: Symbol of Scientific Excellence

On September 10, 2008, the largest and highest-energy particle accelerator known as the Large Hadron Collider (LHC) ran its first test. This gigantic experiment, which contains a tunnel that is 17 miles in circumference, is expected to investigate the validity (and limitations) of our current model for the basic forces of nature and for the most fundamental particles.

I was delighted to read in the description of the experiments, the two paragraphs that I enclose below, one from the New York Times, and the other from the Washington Post.

New York Times

“Eventually, the collider is expected to accelerate protons to energies of seven trillion electron volts and then smash them together, recreating conditions in the primordial fireball only a trillionth of a second after the Big Bang. Scientists hope the machine will be a sort of Hubble Space Telescope of inner space, allowing them to detect new subatomic particles and forces of nature.” (Read full article)

Washington Post

“…astrophysicists have observed that visible matter accounts for only 4 percent of the universe. By looking at gravitational effects — for instance, how fast galaxies spin — they can guess that there is more stuff out there than they can see. But what is this “dark matter?” Could dark matter be composed of “supersymmetric” particles, which might pop up in the collisions at CERN? For this reason, some people have called the Large Hadron Collider the ‘Hubble telescope of inner space’.” (Read full article)

Once again, the Hubble Space Telescope, is given here as a symbol of scientific excellence, and as the discovery machine that EVERYONE can recognize.

Science Instruments – Repair vs. Replace

Recently, several people asked: Why not replace the two instruments we’re repairing with new ones and why can’t we take the two science instruments inside the Shuttle and work on them there?

This is such an excellent question! The answer is truly an engineering marvel, so thank you for asking.

Hubble’s instruments were designed for easy removal and astronauts have removed radial and axial instruments on previous repair missions to Hubble. So, why aren’t we doing the same thing this time? Time is the answer.

The most valuable commodity on-orbit besides the astronauts themselves is the astronauts’ time. Every second of their time is choreographed more closely than an Olympian’s gymnastic floor exercise. Just as the gymnast’s every motion is fixed in her or his mind, the astronaut’s every motion outside the Shuttle is practiced so that a moment is not wasted.

When the spectrograph, STIS, failed, engineers led by Mike Weiss at Goddard, looked at every possible way to fix it, including the ones you’ve mentioned such as bringing it into the Shuttle Cargo Bay. But Mike found that “this approach would have taken about 2 additional hours of EVA time and would have required additional hardware to serve as a work bench. Pulling out the entire instrument would also mean overcoming potential contamination and electrostatic discharge concerns.”

I can’t resist taking this opportunity to talk about the symbiotic relationship between humans and their almost-robotic tools one more time! The NASA engineers surmounted yet another hurdle with tool design. If you’ve pulled electronics boards out of your computer, you’d think it might be pretty easy to do on-orbit. But Hubble has something called “wedgelocks” to make sure the electronic boards don’t rattle around on-orbit and so that there’s a path for heat to sneak out, keeping the boards cool. Imagine how frustrating it would be to pull out a stubborn electronics card in bulky gloves on Hubble! Resorting to swearing is usually the path we earthlings take on the ground. Somehow, it always helps, but it won’t help much on-orbit with Hubble.

So, NASA developed an extraction tool to neatly pull out a board. That tool was tested with the most stubborn test board ever made, and came out with flying colors and little debris.

Now that we know how to gain access to failed cards inside the instruments, pull them out and replace them, and put on a new simple cover, our marriage between tools and humans is complete. As Mike joked, the Hubble commercial might go like this: EVA Set-up — 3 hours. Pull and replace failed electronic cards — 15 minutes. Resurrect Science — Priceless.

Here’s Mike Massimino practicing with the mini-power tool working on a test article.

I just love getting questions like this one that help us all think about the science and engineering marvels we’re creating today. I only wish I could start my career all over again and see what the next 30 years bring.

Colleen